Diavision



June 8, 1937. A. J. CAWLEY DIAVISiON Filed Jan. 30, 1930 2 Sheets-Sheet. l

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DIAVISION Filed Jan. 30, 1930 2 Sheets-Sheet 2 9 INVENTO UNITED STATES PATENT OFFIC The invention relates to the perception oi obects by means of electric waves which are of a ength greater than light waves, particularly hose of small wave length. permitting navigation .0 go on in harbors and the like at a normal rate n heavy mists. Briefly it relates to the percepion of electrically conducting media through ionconducting media by means of radio waves. :onsequently one of its modifications comprises ;he detection of metallic objects in a brick. con- :rete or wooden building. Many other similar ises will immediately suggest themselves.

An invisible image is formed by means or a lens, and this is rendered visible by means of stationary or moving resonators placed in the image field. Those resonators are provided with means for converting electrical energy into visible light. an auxiliary vacuum tube reception detectoramplifier apparatus may be used to operate in synchronis'm with the apparatus in order to obtain a more brilliant image.

A series of resonators is provided in one modification, which may be used without the electric wave forming means, whereby it is possible to detect both the direction and identity or the source of the waves being received.

Radio waves of a known frequency and plane of polarization are directed by means of suitable reflectors upon the objects to be perceived. Coils. or separate electrodes of suitable irequency or tuning characteristics to respond in the greatest degree to those waves are placed in a'position to further respond with the great.- est facility to the waves. due to the position of their vibration or polarization. The coils or resonators in one modification are made movable in the visual field to attain economy in construction, as one moving coil takes the place of many stationary coils.

Reference is to be had to the accompanying drawings forming part this specification. in which like reference characters have similar meanings in all oi the views. and in which.

Figure 1 is an elevational view of the space in which the visual image is to be formed, showing the arrangement oi the electrodes which are here illustrated as being unconnected. which detect the incoming waves and render the gas luminous. Figures 10. lb. lo and id illustrate different modifications of the manner of connecting the resonator;

Figure 2 is a sidefelevationai viewoi another modification, partly in cross section of the gas space which is rendered luminous by the waves. showing the resonators which coact with the so, am. t (Ci. 259-1) No. @263 e r l.

incoming waves. The auxiliary means for detecting the incoming waves and assisting the gas space and resonators in rendering them visible is also shown. Figures 2a and 2b are elevational views, partly in cross-section, illustrating modifications having special arrangements of the electrodes and resonators.

Figure 8 is a side elevational view of an apparatus partly in cross-section, which may be used without an electric wave lens for showing the direction and identity of the source oi inwaves.

Flgure c is an exaggerated elevational side view of a resonator coil and its surrounding ionized gas space, a large number of such coils being used to render a luminous image of objects.

Figure 5 is an illustration of a modification or the complete system in use, showing the transmission of the electromagnetic wave beams, their concentration and dirlgibility. their focusing into an invisible image. and the rendering of this image visible by means of rotating coils and neon tubes.

Figure 6 shows an illustration of one of the carriers for moving the coils and tubes through the image field in a definite direction and position, the latter being that giving the greatest response to the waves: it, together with Figures 60,612, Go and 6d, shows the arrangement of the coils and carriers; Figure 6c shows one of the many ways in which the coils may be attached. In those modifications.a diskisusedasthesupp rting and moving medium.

Figures '1, 7a, 7b, 7c and id show some of the many modifications oi the coils and luminous tubes that may be utilized without departing from the spirit oi the invention.

FigmeBisanillustration oithecoilsand luminous tubes attached to a carrier arm.

rigureilisaniilustrationoraspecialtype oi rotatable element for conva'ting the invisible image into a visible one.

Figure 9a illustrates a modification of Figure 9.

line arrangement and operation or the cameralike structure for rendering an electric wave image luminous was described in my copending application or October 20, 1921, Serial Number 509.168. and is also described in my copending application, Serial No. 528,791, of March 19, 1981,

which is also a continuation-in-part application at the 1921 application. It depended upon the fact that scientists have formed an image by means or large lenses oi bitumen or other electrlc wave permeable substance. in the same manner as Hertz has demonstrated their retrangibility by means of prisms of this material. The type of resonator there described is shown in Figure 2. It is 2, preferably insulated conductor connecting electrodes in an ionized gas cham- 5 bet. Figures 1, 1a, 1b, 1c and 1d illustrate various means of connecting electrodes 6 by means of those resonators, or conductors 8. Figure 1 illustrates a modification in which the electrodes are unconnected. The incoming electric waves 10 generate electromotive force, and a consequent current in them. The current passes through an ionized gas space I! with great case, due to the low pressure existing in this space. At 5 in Figure 1b a diagonal arrangement of resonators, such as 8, 8a, 8b and 8c of Figures 2, 2a and 2b is shown. At 9 of Figure 1c another vertical and horizontal arrangement is shown. At ill of Fig- W ure 1d still anothermore complicated arrangement is illustrated. Figure 2 shows that the source of power is connected by means of coils i to electrodes 1, and these latter connected directly with the contained ionized gas. This arrangement may be compared to a quenched spark gap, as many small metallic particles are provided to conduct the charge or current, but of course with the distinction that the air or neon, helium, etc., is of low pressure and readily permits the flow of proper electric currents. Id of Figure 2 is a detector amplifier and modulator, if desired, arrangement for producing synchronous electrical currents in space l2, and as a result of capacity in resonators 8, 8a, whether simply straight conductors preferably insulated, or coils of fine wire. If I! is placed in proper adjust ment with reference to the incoming waves, it will act to keep the gas space l2 and associated resonators in such electrical condition that a very slight current is necessary in resonators, such as 8a, 8b, etc., to generate sufllcient intensity to represent the "high lights of the image of electric waves. By adjusting either coil or detector amplifier, a condition is maintained wherein there is always an almost imperceptible. or a sub-visual luminosity. The operation of the resonators by means of the current passing in gas space l2 will be understood by considering that they act in a manner dependent upon their capacity, and by the fact that a passing current always influences neighboring circuits. By placing conductors 8 in front of electric wave permeable plate 2, they will be in unhindered contact with the wave at its fullest intensity, as when placed in the gas space, due to the fact that there is no such thing as a perfectly transparent substance for electric waves, be they light waves or other waves. They are really subjected to waves that have suffered more or less by absorption in 2 when placed in the gas space.

In order to further understand the operation of the apparatus illustrated in Figures 1, 1a, 1b, 1c, 1d, 2, 2a and 2b when used in connection with the camera-like structure of the above mentioned application, reference must be had to Figure 4. Coil 8:: may be made of many turns of fine wire, if desired, and since it is placed in the camera in a position in which its plane is at right angles to the focal plane of the electrical image, constitutes a virtual wave detector, as in this position it receives electric waves in such manner as to permit them to generate the greatest possible currents in vertical members 3 and I. Moreover, they have a specificity for waves of a certain length, but are not limited in their reception thereto. Ii. the incoming wave is of 7 :mch a length that its crest is at 4 wh n trough is at 3, then the greatest possible current is gel erated. Waves of less than a centimeter in leng have been generated by use of apparatus utilizii spark gaps. If the distance between 3 and is a half-centimeter, the sharpest reception wou be for waves of one centimeter. Waves of mm greater length will afiect the apparatus. But

suitable reflectors are used with the apparat for concentrating the waves being sent out in a beam, as by reflectors made of wires, and ha' ing the waves of short wave length, very mul shorter than any ever even attempted commercia ly, a new type of wireless communication could] built up. If objects could be perceived at a di tance of flve miles, tremendous advantages wou result in the speeding up of navigation in ha: bors, and in theg railroad traflic... of the countr Very short waves like those are not used for ti commercial transmission of messages. Exceei ingly short waves are desirable in the formatic of an image, due to the refraction require Much longer waves may be detected by use oi.

device like that of Figure 3. The apparatus cor sists of a number of cells 8, 8', and 8" with ti usual gas space l2. However I1 is a reflectr of electric waves, and by reflecting them back i the direction in which they came, there will I a superposition of crest upon crest at the vertic: portion corresponding to 4 of Figure 4, and

greater concentration showing direction of ti. signals, in addition to their sense. If the dis tance between portions as of 3 and 4 is one half meter, the wave length which gives the great est luminosity is one meter. This would air the identity of the sender, ii each light bone or the like had a definite known wave length.

If the coils, such as 8a, Figure 4, have man turns, then the greater the number oi verticz members in 3 and 4, the longer will be the wav length that it will respond to. Several conduc tors in 3 and 4 correspond to a conductor 1 general, equal in length to the sum of thel lengths. Thus, though 4 may be extreme! short, it would equal an antennae of many time its length in wave reception. All of those coil: whether consisting of several turns or whethe consisting of an upright single insulated mem ber, correspond to a resonator such as those use by Hertz, but with the distinction that this con sists of a column of gas instead of a metal wir with two spark balls enclosing the gap. The col umn of gas is a conductor of electricity, and ma: have electric currents generated in it like an: conductor by means of electric waves. By hav ing many turns of fine wire in the coil, a curren of high electromotive force is generated, in i by the incoming electric waves, and this aids ii forcing it through the gas. The coils, therefore may be very minute and thus give great detai to the image. The coil, moreover, has distributel capacity as well as inductance, which is in creased by keeping the turns close together.

Gas space I! may be made more sensitive t4 electrical discharges if desired by causing th rays from the ultraviolet lamp to fall upon it and thus render the apparatus far more sensitive. The electrodes 6 may be made of a meta if desired. such as that used in certain lamps, 01 sources of ultraviolet light.

The insulated vertical member 0 has utility in the -reception of short waves, as a coil 01 ismlagt inductance and small distributed capacity The apparatus may be regarded as 9. development of the apparatus of Hertz. Hundreds o area resonatorsareusedjustasheusedthembut are arrangedin aiocal plane. Instead ofhis feeble means of generating oscillations, large, powerful means are used having the same strength as those used commercially to generate the much longer waves which are now used for wireless communication. Those short. quasioptical waves will be concentrated in the form of a beam by means of suitable metallic wire, or other reflectors in order that all of the energy may be concentrated in a definite direction. Waves a few millimeters long have been generated by use of spark gaps. Short waves'readily permit their use in forming images by means of suitable lenses.

Ashore station might send a beam at least as tar as light is ordinarily discernible by ships in clear weather. That is, it would have the same range as a lighthouse has in clear weather, but of course its signals would be discernible in all kinds of weather.

Each coilmaybealsolookeduponasaminute direction finder, and therefore is placed at its most sensitive position with regard to the incoming electric waves forming the image.

The camera body should be electric wave proof, and this may be accomplished in various ways, one of which is by covering it with metal foil of suitable thicknes in order to protect the gas space from stray waves.

Figure 5 is an illustration of the application of the apparatus to discerning the presence and position of steamships during logs and mists. Any generator of high frequency electricity of suitable type is indicated by 26. A row of short wave generators, such as short conductors, or a plurality of Rhighi gaps is indicated at 24; this may consist of many rows of many generators. These are connected to the source of high frequency electricity 2G. The waves thus generated are reflected by the cylindrical reflector 23. They are somewhat similar to generators described in my application Serial Number 376,743, Power transmission system, filed July 8, 1929. The waves are polarized in a definite plane, and ii. the receiving resonators to be described later are placed in a position to respond most readily to those waves, great sensitiveness is given the apparatus. It is to be noted that reflector 23 is cylindrical and parabolic. A reflector 22 is also shown that is spherical and parabolic, the generators in this are placed in various positions and the emitted and directed waves are unpolarieed, similar to ordinary light. The apparatus for generating and directing the electromagnetic waves may be placed on the ship or may be placed at a central point in a harbor and used to "illuminate" the entire harbor. The reflectors such as 22 and I! may be made of metal of any desired form, such as of metallic wires. The waves are directed upon any object desired, such as ship S. The waves are refl cted from the conducting portions of the ship S into the lenses L of camera-like structure ll, IS, 20. The lens, or lenses L may be made of paraflin, bitumen, glass, ebonite. etc. One or more lenses, having the same or difierent refractive index may be used, as in ordinary vkible light optic. The body of the camera should be either made of metal or covered with a suitable metallic sheeting or foil. A telescopic joint is indicated at I8, and this type of structure may be used. As an alternative structure, a bellows made of metallic sheeting or foil, or of other material andcover'ed with metallic foil. is illustrated at is. The camera housdisk d carrying a series of coils.

6a and 6d represent the side of the disk that.

ing or body may be made very long and tapering, as indicated by the right hand portion of Figure 5. This is indicated by 23. This will compensate for the extra long wave lengths used as compared to visible light waves.

Instead of theplane polarizing reflector such as 23, we may have the waves generated in all planes. In other words, the electromagnetic waves may be unpolarized, and a spherical reflector such as 22 provided. This is used to direct the waves in desired directions, such as on the object S.

There is fitted into the end oi the camera-like structure just described the different modifications of apparatus described and illustrated in Figures 1 to 4 inclusive, also that described in connection with Figures 6 to 9 inclusive. However,'the apparatus shown in Figures 1 to 4 is rather expensive, due to the fact that very many resonators are used. A less expensive apparatus is shown in Figure 5. coils each provided with a spark gap g and a neon or similar tube which becomes luminous when traversed by the current that is generated in the coil c. The tube is designated by reference character 1.. These coils are arranged on arms 25, of which there may be a plurality. Th arms are readih rotated by means of motor 2!, which rotates the shaft to which arms 25 are attached. In Figure two arms are shown at right angles to each other, each carrying a number of coils. If the beam of waves is plane polarized, as by the reflector 23, then the coils on the horizontal arm shown in the figure will respond vigorously and this will be indicated by the glow of the neon tube t. If, however, the waves are vibrating in all planes, i. e. they are unpolarized, the coils will be activated in any position, and the tubes will glow correspondingly. In other words, the tubes will all glow, only those being extinguished or partly extinguished as are in the low lights of the picture. Therefore, when unpolarized waves are used, the typeof receiver showninFigure5,inwhichthearms25carry the coils c and tubes t through an entire circle, maybe used. Thatis,eachcoildescribesacomplete circle, and the image is built up in a series of concentric circles. If, however, a transmitter such as that shown at 23 and a is used, the waves are polarized in a vertical plane, and only the coils shown in the horizontal arm of Figure 5 (shown in cross section) would give a spark at their spark gap. and cause their tubes t to glow. Obviously, as each arm assumes a certain P tion on being rotated, the tubes borne by it will glow. For this reamn. an arrangement similar to that used in television is employed, whereby the arms 25 are made of much greater length, and the visual field is small compared with their length. Armsordisks,suchasdofPigure6 may be used.

figures6,6a, 6b,6cand6dgiveaclearerillustration of this. Here the visual field is represented by I somewhat similar to the general methods of television. It will be noticed that thecoilscare shown withtheirspark gapsgin a horizontal l here shown) or other plane. That is, they traverse it in a definite direction, and their paths are straight lines. Arms or disks may be used. Figures 6, 6a, 6b, 6c and 6d show the Figures 6.

faces the lens L of Figure 5. The spark gaps g are clearly illustrated. It will be noted that they traverse the image field I in a horizontal posi- Thisconsistsofaseriesot tion. Figure 6b shows the side of the disk racing the observer and the tubes t are plainly indicated. It is the luminosity in those tubes that produces the luminous image. The disk acts to hide the spark produced in the gap. The face of the disk facing the observer may be painted or otherwise colored black or any other desirable color to intensify the illumination of the tubes t. It is to be noted that the visual field or the area where 10 the image is to be produced is much smaller than the diameter of the disk d. All coils traverse the field in the same lines, for instance, here they are all horizontal. More than one row of coils may be used, and they may be arranged in a "staggered manner so that a real fine, detailed, sharp image is produced, if desired. Or, they may be arranged in a spiral line. Figures 6, 6a. and 6d show both of those arrangements. Figure 6c shows a plan view of one of the coils, and indicates the mannor of coil 0 passing through and being supported by disk d; it also indicates that the spark gap g is located towards the lens L and that the neon or other tubet is located on the opposite side of the disk or other support. This neon tube t may be attached to the coil 0 in any manner and at any portion of the coil desired. It may be connected by wires to the coil at any portion of the coil 0, the coil being otherwise entirely separate therefrom. It is obvious that the vertical row of coils of Figure 6a is traversing the image field, while the row shown at an angle of 45 degrees thereto will traverse the field in such manner that each tube will "draw" or scan luminous lines between those already drawn" by the vertical row. As many coils as desired may be employed and in any configuration desired, with the result that almost any degree of detail may be attained.

It will be observed that in order to light the neon or other tubes in the field j of Figure 6, that the transmitter 24 of Figure 5 should be turned in a horizontal position. In this manner all of the energy radiated from conductors 24 is made to give the fullest efiect upon coils c with their attendant luminous tubes t. All of the energy from 24 is sent in a definite direction by reflector 23, instead of being scattered in all directions as in broadcasting. Furthermore, this energy is concentrated, and is also polarized in a plane that will give the greatest results at the receiving coils c.

Figures '1, 7a, 7b, 7c and 7d show some of the types and manner of arrangement of the various resonators. Figure '1 shows a coil somewhat like that of Figure 4. The spark gap (in air) is shown at the top or the figure, while the neon or other tube t is shown at the opposite end of the coil. Fig. 7a is a side elevation of Figure 7. The carrier arm is shown in cross section in the form of a U in the center of the coil. It is to be noted particularly that the tube t may be attached to any portion or the coil c desired to produce the most desirable illumination. The coil in this figure is shown attached to the tube by a shunting wire circuit.

Figure 7b shows a single turn coil. The tube t is here shown as forming a part of the call, but may be shunted across any portion of the coil desired, and is not limited to the form shown. Figure 7c shows a single turn coil which is entirely in front of the carrier arm. while a tube t of neon or other tube, is shown to the rear of the arm, and this tube is connected in shunt to the coil 0. Figure 7d shows a circular single turn 1'6 coil which surrounds the carrier arm (here shown as T shaped), while the neon or other tube t is shunted around the main coil. Some of the many possible forms of the carrier arm 25 are shown in this figure.

Figure 8 illustrates a carrier arm with some of the many possible coils c and associated neon or other tubes t that may be used. a is the shaft upon which the arm is mounted, and which rotates together with the coils at a suitable speed. If plane polarized waves are used, only a small portion of the arm is provided with coils c. However, both ends of the arm may be provided with coils in such manner that the lines described by the coils on one end may pass between the lines described by those on the other with the result that more lines, and consequently more definition are added to the picture. If heterogeneously polarized waves are utilized, the coils c are placed all along the full length of the arm, so that the image is made up of concentric circles of light produced by the neon tubes. Moreover, those concentric circles are staggered in the manner just described in order to produce a greater number of lines in the visual field, and thus give more definition to the image.

It is to be noted that the devices illustrated in Figures 1 to 4 are to be used in the camera-like structure illustrated in Figure 5. In other words the elements may be stationary or movable. It is also to be noted that the invention also includes a plurality of stationary elements of a nature similar to those illustrated in Figures '7 and 8, which contain a spark gap in addition to an illuminable element. Itis well known that the spark gap is important, due to its function of building up the electric charge that is collected from the electromagnetic waves that traverse the coil.

This application is a continuation in part of my application Serial Number 509,163. filed October 20, 1921. for Electric wave device, and since abandoned, and contains subject matter disclosed in part by my informally filed application of September 29, 1922 for Hertzian wave apparatus.

Figure 9 shows a plurality of metallic elements 26 connected by wires 28 and 29. Figure 9a illustrates a modification in which the metallic elements 26 are unconnected. This constitutes a rotatable arm consisting of a glass or other transparent tube 21, which contains neon or other gas partially exhausted to produce the greatest illumination (at low pressure). This is mounted upon shaft 30 carrying insulated collector ring 32, together with brush 3|. Current is conveyed through 3|, 32, 28 to one series of elements 26, and through shaft 30, wire 29 to the other series of elements. Thus the auxiliary current may be passed to the electrodes. Either 30 or 3| may be connected to the ground if desired. This rotating element is placed in the plane of the invisible electromagnetic wave image to render it luminous. As shown in the figure, in the upper portion of the tube 21, the electrodes 26 maybe unconnected to the external circuit. In such case, the rotating element would simply consist of a rotating tube carrying a plurality of unconnected electrodes in neon or other suitably illuminable gas.

Having described my invention, I claim as new and desire to secure by Letters Patent:

1. In combination: means for forming an invisible image of electromagnetic waves reflected from objects and a plurality of resonator lights placed substantially in the plane of said invisible image tonroduce a visible image.

2. In combination: means for forming an inisible image ofelectromagnetic waves reflected romobjects and means placed substantially in he focal plane of said invisible image to convert aid invisible image into a visible image by the notion of said electromagnetic waves constituting and invisible image upon the said means.

3. In combination: means for forming an in- 'isible image of electromagnetic waves reflected rom objects and means placed substantially in he plane of said image for converting said inisible image into avisible image, and means for #xcluding extraneous electromagnetic waves from aid image plane.

4. The method of perceiving objects by means f radio waves, which consists in generating elecromagnetic. waves, concentrating said waves into I, dirigible beam directing said beam upon deired objects in order that they may be reflected herefrom, converging said reflected waves into m invisible image, converting said electromagietic wave image into a visible image by suitable 'esonator-light elements.

5. In combination: means for forming an inisible image of electromagnetic waves reflected 'rom objects and a plurality of moving resonatorights placed substantially in the plane of said nvisible image to convert said invisible image nto a visible image.

6. Lin-combination: means for forming an indsible electromagnetic wave image, a rotatable element substantially in the plane of said image :arrying a plurality of resonators, each of said 'esonators having associated therewith an illuninable element which becomes illuminated by be current generated in said resonators, thus :onverting said invisible image into a visible mage. V

'7. A luminous image forming device consisting if a rotatable disk, said disk being placed sub- :tantially in the focal plane of an invisible elecromagnetic wave image, a plurality of resonatoright elements borne on said disk and arranged n staggered relation.

8. A luminous image forming device for conrerting an invisible electromagnetic wave image nto a visible light image consisting of a disk, a :vlurallty of resonator-light elements arranged n a spiral line on said disk, said device being placed substantially in the focal plane of an nvisible electromagneticv wave image.

9. Means for converting an invisible electronagnetic wave image into a visible light image, :onsisting of a rotatable element, a plurality of elements borne on said rotable element and each :onsisting of a coil having a .spark gap included .herein with an associated circuit containing an lluminable lamp.

10. Means for converting electromagnetic waves nto light when rotated substantially in the plane if an electromagnetic wave image comprising a rotatable element consisting of an arm, a plurality of resonators borne on said rotatable element, each of said resonators being provided with an illuminable element, for the purpose of renderinbg said invisible electromagnetic wave image visi le. ,7

11. Means for converting electromagnetic waves into light when rotated substantially in the plane of an electromagnetic wave image comprising a rotatable disk, a plurality of resonatorlight elements borne on said rotatable disk and arranged in staggered relation.

12. A device for rendering an invisible electromagnetic wave image visible when placed substantially in the plane of said image which consists of a plurality of elements for transforming the said electromagnetic waves into electric currents and for converting said currents into visual light.

13. A device for rendering invisible electromagnetic wave images visible, which consists of means for forming invisible electromagnetic wave images, a transparent body having a chamber therein filled with an illuminable gas at suitable pressure and a plurality of metallic bodies, said bodies corresponding and coinciding with the elemental areas of said images, electrical discharges taking place between said bodies resulting in luminous discharges in said gas in accordance with said invisible image, thus producing a cor-. responding visible image.

14. A device for converting an invisible electromagnetic wave image into a visible image consisting of means for forming an invisible electromagnetic wave image, a plurality of electrodes arranged in the form of a plane corresponding to the plane of said invisible image, said electrodes having a number corresponding in general to the number of elemental areas of said invisible image and enclosed in a transparent body containing a suitable gas at a suitable pressure to produce a varying glow therein in accordance with said invisible image, said glow being due to the electric currents generated in said gas by said electromagnetic wave image, the result being a visible image.

15. A device for converting an invisible electromagnetic wave image into a visible image, consisting of means for forming an invisible electromagnetic wave image, a transparent body containing a suitable gas at a suitable low pressure for the production of glow discharges placed in the focal plane of said invisible image and a plurality of metallic bodies arranged in a plane in said gas, said bodies having a number corresponding in general to the number of elemental areas oi said invisible image.

16. A device for rendering invisible electromagnetic waves visible, consisting of a lens forming an image of electromagnetic waves, a plurality of metallic bodies in a body of illuminable gas and arranged in the form of a plane therein,.

said bodies being divided by electrical connections into two groups, a source of biasing current connected to said groups of electrodes, the energy of said waves charging said conductors and causing a luminous discharge taking place in said gas corresponding to the distribution of the electromagnetic wave energy in said image, said luminous discharge constituting a visible image.

ALOYSIUS J. CAWLEY. 

